DTC Troubleshooting
DTC Troubleshooting: P0497
DTC P0497: EVAP System Low Purge Flow Detected
Special Tools Required
- Vacuum pump/gauge, 0-30 in.Hg, Snap-on YA4000A or equivalent, commercially available
- Vacuum/pressure gauge, 0-4 in.Hg 07JAZ-001000B
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information. Reading and Clearing Diagnostic Trouble Codes
1. Turn the ignition switch to ON (II).
2. Clear the DTC with the HDS.
3. Select EVAP FUNCTION TEST in the INSPECTION MENU with the HDS.
Is the result OK?
YES - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the EVAP canister purge valve, the FTP sensor, and the PCM.
NO - Go to step 4.
4. Turn the ignition switch to LOCK (0).
5. Check for a poor connection, a blockage, or damage at the EVAP canister purge line between the throttle body and the EVAP canister.
Is the line OK?
YES - Go to step 6.
NO - Reconnect or repair the EVAP canister purge line, then go to step 24.
6. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B).
7. Disconnect the vacuum hose (A) from the purge line (at the EVAP canister side), and connect the vacuum pump/gauge, 0-30 in.Hg, to the hose with a T-fitting (B) as shown.
8. Turn the ignition switch to ON (II).
9. Apply about 2 kPa (0.6 in. Hg, 15 mmHg) of vacuum to the hose.
10. Select EVAP PCS ON in the INSPECTION MENU with the HDS.
Does the vacuum release immediately?
YES - Go to step 15.
NO - Go to step 11.
11. Select EVAP PCS OFF in the INSPECTION MENU with the HDS.
12. Disconnect the vacuum hose (A) from the EVAP canister purge valve (B). Connect a T-fitting (C) from the vacuum gauge, and connect the vacuum pump/gauge, 0-30 in.Hg, and EVAP canister purge valve as shown.
13. Apply about 2 kPa (0.6 in.Hg, 15 mmHg) of vacuum to the hose.
14. Select EVAP PCS ON in the INSPECTION MENU with the HDS.
Does the vacuum release immediately?
YES - Check for a blockage in the vacuum hose between the EVAP canister purge valve and the EVAP canister, then go to step 24.
NO - Replace the EVAP canister purge valve, Service and Repair then go to step 24.
15. Connect the vacuum pump to the vacuum hose (A) as shown.
16. Start the engine, and let it idle.
Is there vacuum?
YES - Go to step 17.
NO - Check for a blockage in the vacuum hose between the EVAP canister purge valve and the intake manifold, then go to step 24.
17. Turn the ignition switch to LOCK (0).
18. Remove the FTP sensor with its connector connected. Service and Repair
19. Connect a T-fitting (A) from the vacuum pump/gauge, 0-30 in.Hg, and connect the vacuum pump to the FTP sensor (B) as shown.
20. Turn the ignition switch to ON (II).
21. Check and record the FTP SENSOR reading in the DATA LIST with the HDS.
22. Slowly apply about 1.3 kPa (0.4 in.Hg, 10 mmHg) of vacuum to the hose.
23. Check the FTP SENSOR in the DATA LIST with the HDS.
Does the value change?
YES - Check for debris or a blockage at the EVAP canister port, then go to step 24.
NO - Replace the FTP sensor, Service and Repair then go to step 24.
24. Turn the ignition switch to ON (II).
25. Reset the PCM with the HDS.
26. Do the PCM idle learn procedure. PCM Idle Learn Procedure
27. Do the EVAP FUNCTION TEST in the INSPECTION MENU with the HDS.
Is the result OK?
YES - Go to step 28.
NO - Check for poor connections or loose terminals at the EVAP canister purge valve, the FTP sensor, and the PCM, then go to step 1.
28. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0497 indicated?
YES - Check for poor connections or loose terminals at the EVAP canister purge valve, the FTP sensor, and the PCM, then go to step 1.
NO - Troubleshooting is complete. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.